Questions:
1. What kind of proofs are you generating? Contract color or digital dylux?
2. Are you using uni-directional or bi-directional printing?
3. What resolution? 720? 1440?
4. Which Quality setting, Ink Table, and Proofer Profile are you using?
5. How long would it typically take your 9900 to print a single 8.5 x 11?
6. Are you printing directly via TCP/IP or using a Windows Spooler?
As for the screen tint, does the tint appear as a background flood everywhere? If so, this might stem from using Absolute Colorimetric rendering intent. Try switching to Relative Colorimetric.
Best regards,
hp